In electrical engineering a resolver is an electromagnetic measuring transformer for converting the angular position of a rotor into an electrical quantity or into electrical signals. These signals are ultimately used for determining the relative angular position between two subassemblies which are able to rotate relative to each other, e.g., two machine parts rotatable relative to each other. In the present application, the term resolver also encompasses measuring converters, which are referred to as synchros or rotary resolvers.
In a resolver, offset stator windings which enclose a rotor situated inside the housing with rotor windings are often disposed inside a housing. In this case both the stator windings and the rotor windings are disposed on a laminated core, which acts as guide for the magnetic flux. The laminated cores are made up of a multitude of individual sheets, which are usually produced from a magnetically soft material in order to increase their electromagnetic effect.
In brushless resolvers, a rotating winding of a transformer transmits the rotor voltage to a stationary winding of the transformer in contactless manner. The windings on the stator side and the rotor side are normally disposed inside a housing of the transformer.
Such resolvers are often produced in large numbers, so that a simple, automated production is called for, if at all possible.
Resolvers are known whose housings for the windings of the transformer are produced by turning processes. This known construction has the disadvantage that the current consumption of the resolver is fairly high due to relatively low efficiency of the transformer, and that the measuring precision is ultimately limited. In addition, turned housing components are quite expensive in the production.
European Published Patent Application No. 1 302 953 describes a brushless resolver, for which a housing for the windings of the transformer is made from a deep-drawn component and a planar component.
Such a construction has disadvantages with regard to the measuring accuracy and, furthermore, can be produced or assembled only at relatively high cost.